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Microvascular occlusion syndromes Flashcards

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1
Q

HITS epi

A
  • 10X higher in unfractionated heparin compared with LMWH
  • F>M
  • rare in pregnancy
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2
Q

HITs pathogenesis

A
  • Platelet 4 factor is released and complexes with heparin –> rapid IgG antibody response within 5-7 days develops
  • Immune complexes develop –> activating platelets and monocytes
  • These activated platelets aggregate and produce platelet microparticles which generate thrombin, and thrombocytopaenia develops
  • Activated monocytes and endothelial cells also increase their expression of tissue factor –> thrombin production and vascular occlusion
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3
Q

HITS clinical

A
  • Timing
    • 5-10 days after heparin starts
      • if have had heparin in the last 90-100 days, then HITS can develop within hours after re-exposure
      • rarely can have anaphylactoid reaction within 30 minutes of a heparin bolus
    • Delayed-onset: lesions can occur up to 3 weeks after exposure to heparin
    • Atypical scenarios:
      • Chronic heparin –> can trigger within 5-10 days
      • sometimes without heparin, major surgery or bacterial infections can trigger a spontaneous or autoimmune HIT syndrome
  • Cutaneous
    • Tender, sharply demarcated, non-inflammatory and purpuric or necrotic, retiform
    • Can occur at sites of S/C injection, or distant to heparin infusion
  • Platelets
    • Don’t often get thrombocytopaenia on bloods, although there is a consumption of platelets
    • Decline in platelet of >50% from highest count should prompt consideration
  • Cx: vascular occlusion to any limb or organ
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4
Q

HITS pathology

A

non-inflammatory occlusion of blood vessels and ischaemic necrosis

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5
Q

HITS dx

A

You can test: presence of anti-PF4 heparin complex antibodies –> can do via ELISA

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6
Q

HITS rx

A
  • Cease heparin
  • Argatroban: treatment of HITS, is a direct thrombin inhibitor
  • Also effective: danaparoid (Xa inhibitor), fondaparinux and bivalirudin
  • need anticoagulation for 3 months with non-heparin agent
  • Vitamin K blockers are contraindicated: increased risk of developing venous limb gangrene secondary to decreased Protein C
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7
Q

Essential thrombocytosis epi

A
  • PCV and essential thrombocytosis are more common in women
  • > 50 years, incidence increases exponentially after 60 years
  • have an increased CVS mortality risk
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8
Q

Essential thrombocytosis pathogenesis

A
  • essential thrombocytosis followed by PCV more likely to develop
  • JAK mutation present in 90-95% of PCV patients, 50-70% of essential thrombocytosis and primary myelofibrosis
  • MPL and CALR more commonly in essential thrombocytosis and primary myelofibrosis
  • In these disorders, platelets can function abnormally –> occlusion or haemorrhage
    • When platelets 400-1000 then thromboembolism is common
    • When platelets 1000-2000 then bleeding is more common
    • Acquired von Willebrand occurs when the platelet count is >1000
  • When the platelet count is within a normal range of a myeloproliferative neoplasm, the risk of thrombosis is uncertain
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9
Q

Essential thrombocytosis clinical

A
  • Cutaneous in 20% of patients
    • Purpura
    • Haematomas
    • Livedo reticularis
    • Erythromelalgia
      • Intense burning and paroxysmal bright erythema of the distal extremities
      • can occur with any myeloproliferation or myelodysplastic disorder if the platelets are high enough
      • platelet mediated acral vasodilation, inflammation and microvascular occlusion
      • secondary responds well to aspirin
    • Raynaud
    • Urticaria
    • Vasculitis
    • Leg ulcers
    • Gangrene
    • Superficial thrombophlebitis
  • CML often has elevated neutrophil counts, eosinophil or basophil counts
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10
Q

Essential thrombocytosis histo

A
  • microvascular occlusion of dermal vessels or subcutaneous arterioles
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11
Q

Essential thrombocytosis rx

A
  • Can give low dose aspirin
  • For high risk - >65 with PV or >60 with ET and thrombosis –> low dose aspirin plus cytoreductive therapy
  • refractory prutiis in PCV –> paroxetine, interferon alpha, UVB phototherapy, JAK inhibitor
  • Imetelstat
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12
Q

Paroxysmal Nocturnal Haemoglobinuria pathogenesis

A
  • Mutation ins PIG-A in haemotopoietic stem cells - encodes proteins which are responsible for protecting blood cells and platelets from complement mediated injury.
  • Lack of protection: red cell lysis and activation of platelets
  • X-linked
  • Cause of venous thrombosis is multifactorial, due to microparticle formation from platelets and other blood componenet membranes
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13
Q

Paroxysmal Nocturnal Haemoglobinuria clinical

A
  • Intravascular haemolysis, deficient haematopoiesis and thrombotic tendency
  • can occur with aplastic anaemia, myelodysplastic syndrome
  • Thrombotic events the most common cause of death, and venous thromboses more common than arterial
  • Cutaneous:
    • Haemorrhagic bullae
    • Petechiae
    • Leg ulcers
    • Non-inflammatory retiform purpura
    • Purpura fulminans like presentation
  • Extra-cutaneous: smooth muscle dystonia with dysphagia, abdominal pain and erectile dysfunction, ++ chronic kidney disease
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14
Q

Paroxysmal Nocturnal Haemoglobinuria histology

A
  • microvascular occlusion
  • detection of an absence or severe deficiency of GPI-anchored protein in >2 cell lineages (WCC, RBC) by flow cytometry of peripheral blood is diagnostic of PNH
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15
Q

Paroxysmal Nocturnal Haemoglobinuria ddx

A
  • haemolytic anaemia + pancytopaenia should suggest PNH

- the ddx is super broad

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16
Q

Paroxysmal Nocturnal Haemoglobinuria rx

A
  • Eculizumab: inhibits terminal phase of the complement cascade at the C5 stage, and can reduce intravascular haemolysis and venous thrombosis
  • this can increase the risk of meningococcaemia via C5 inhibition, so make sure they get the meningococcal vaccine 2 weeks prior
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17
Q

Primary thrombotic microangiopathy characterisation

A
  • characterised by microangiopathic haemolytic anaemia + thrombocytopaenia
  • used to be TTP and HUS, but there are just lots of types of primary and secondary
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18
Q

Primary thrombotic microangiopathy inherited subtypes

A
  • ADAMTS13 deficiency - TTP:
    • onset in childhood
    • recurrent TMA, neurologic or other organ
    • Rx: plasma infusion or exchange
  • Complement mediation
    • 90% of inherited cases
    • results in uncontrolled activation of the alternative complement pathway
    • TMA + renal injury
    • Rx: anti-complement: eculizumab, plasma exchange or infusion
  • Metabolism mediated - MMACHC mutation
    • homocystinuria and methylmalonic aciduria from mutation
    • metabolic abnormalities trigger platelet activation
    • Occurs in infancy
    • Clinical: developmental delay, hypotonia, pulmonary artery hypertension, CKD with hypertension and proteinuria
    • Rx: B12, folinic acid, betaine
  • Coagulation mediated
    • Mutation in THBD, PLG and DHKE - encode thrombomodulin, plasminogen, etc
    • results in prothrombosis
    • see in infancy
    • AKI
    • Rx: plasma infusion
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19
Q

Primary thrombotic microangiopathy acquired subtypes

A
  • ADAMTs12 deficiency
    • from autoantibodies leading to inhition of ADAMTS12 activity
    • results in vascular occlusion
    • Adults: more common in women and blacks
    • TMA with thrombocytopaenia, GI symptoms, focal neurological defects, transient renal injury
    • Rx: plasma exchange
  • Shiga toxin mediated - HUS
    • Enteric infection with a toxin secreting strain of E coli or Shigella
    • Early childhood
    • Infectious enterocolitis, thrombocytopaenia, renal disease
    • Supportive care
  • Drug mediated - imnune
    • Quinines, quetiapine, gemcitabine, interferon-beta
    • Adult hood
    • Sudden onset of severe systemic symptoms
    • Stop the drug!
  • Drug mediated - toxic/dose related
    • Multiple drugs: cyclosporin, tacrolimus, VEGF inhibitors
    • Gradual onset renal failure
  • Complement mediated - 10% of cases acquired
    • Antibdoies inhibit complement factor H
    • Reduced inhibition or allternate complement pathway factors –> vessel damage
    • AKI
    • Plasma exchange
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20
Q

Primary thrombotic microangiopathy clinical

A
  • Fever, petechiae, thrombocytopaenia, microangiopathic haemolytic anaemia (schistocytes or framgented red cells prominent on the peripheral smear)
  • Renal disease
  • Neurologic: headache and confusion
  • Macular petechiae: reflect haemorrhage, but occasionally may be from platelet plugging
  • Disease may be subclinical unless triggered by factors such as drugs, pregnancy, AI-CT disease, systemic infections, haematopoietic stem cell transplant, malignant hypertension
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21
Q

Primary thrombotic microangiopathy histo

A

microvascular occlusion of the visceral terminal arterioles and capillaries

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22
Q

Primary thrombotic microangiopathy Ddx

A
  • sepsis syndromes
  • DIC
    • normal or minimally elevated prothrombin time plus profound thrombocytopaenia strongly favours TMA over DIC
  • antiphospholipid antibody syndrome
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23
Q

What are cryoglobulins

A

immunoglobulins that are present in both serum and plasma, and reversibly precipitate with cold exposure

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24
Q

What are cryofibrinogens

A

fibrinogens which precipitate in the cold, are consumed in clotting and therefore detectable only in plasma samples

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25
Q

What are cold agglutinins

A

antibodies which promote agglutination of red cells on exposure to cold

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26
Q

Disorders of Cryoprecipitation or Cryagglutination pathogenesis

A
  • cryoglobulins become water insoluble on exposure to the cold –> increased viscosity
    • Type 1: occlusion
    • Type 2 & 3: immune complex mediated vasculitis –> inflammatory purpura which is palpable
  • When cryoproteins precipitate it results in retiform purpura/necrosis –> reflection of monoclonal immunoglobulins –> type 1 from an underlying plasma cell dyscrasia
  • Immune complex disease results in inflammatory purpura that is palpable –> usually due to Type 2 or 3, due to HCV
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27
Q

Disorders of Cryoprecipitation or Cryagglutination epidemiology

A
  • Cryofibrinogenaemia varies from 0-7% in healthy, and 8-13% in hospitalized
  • Female: male is 1.5-4.5:1
  • can be secondary to lots of things: carcinomas, infectious, autoimmune
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28
Q

Disorders of Cryoprecipitation or Cryagglutination clinical

A
  • Cardinal sign: purpura or necrotic lesions, often retiform, at acral sites of cold exposure
  • Other cutaneous:
    • acral cyanosis
    • Raynaud phenomenon
    • livedo reticularis
  • Type 1 may have secondary vasculitis
  • Type 2 may cause occlusion if they are unstable at close to body temperature
  • With cryofibrinogenaemia –> need clinical correlation as its actually quite prevalent.
  • Cold agglutinins are often asymptomatic, incidental findings such as mycoplasmal infections
    • when symptomatic: haemolysis post cold exposure
    • very rarely, cold exposure can result in red cell agglutination in cold-exposed sites
    • can occur at infusion sites
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29
Q

Disorders of Cryoprecipitation or Cryagglutination histo

A
  • eosinophilic hyaline occlusion of the blood vessels
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30
Q

Disorders of Cryoprecipitation or Cryagglutination ddx

A
  • syndromes of distal occlusion: cholesterol emboli, acral antiphospholipid antibody
  • Pernio
31
Q

Disorders of Cryoprecipitation or Cryagglutination rx

A
  • minimise cold exposure
  • Cryoglobulinaemia:
    • control underlying plasma cell dyscrasia or lymphoproliferative disorder
    • short term: plasmapheresis or plasma exchange
  • Cryofibrinogenaemia:
    • low dose aspirin and steroids
    • Stanozolol
    • Immunosuppressants, plasmapharesis, IV fibrinolysis
    • Thrombotic: anticoagulation
  • Cold agglutinin:
    • cold avoidance
    • Rituximab - 50% response rate
32
Q

Cholesterol emboli epi

A
  • Mean >50 years

- Comorbidities: diabetes mellitus, hyperlipidaemia, hypertension, tobacco use, peripheral artery diease

33
Q

Cholesterol emboli pathogenesis

A
  • severe atherosclerotic disease
  • three settings to fragment cholesterol:
      1. Arterial or coronary catheterization
      1. Prolonged anticoagulation: slowly lyses the clot, leaving exposed areas of the plaque subject to shear stress of arterial flow. Occurs 1-2 months after starting the therapy - ‘warfarin blue toe syndrome’
      1. Acute thrombolytic therapy - given for MI or stroke, can occur within hours to days
  • 20% will have no known inciting event
34
Q

Cholesterol emboli clinical

A
  • Systemic: fever, weight loss, myalgias, altered mental status, sudden onset of arterial hypertension
  • Cx: embolic –> TIA, strokes, renal failures, GI ulcerations, haemorrhagic pancreatitis
  • Cutaneous:
    • Livedo reticualris
    • Cyanosis/blue toes - 30-75%
    • Ulceration - 15-40%
    • Peripheral gangrene
    • Nodules
    • Purpura
  • Can get upper extremity lesions can occur if the plaque originated in the aortic arch
  • Initial diagnosis made in only 35-40% of patients
  • Ix: eosinophilia, hypocomplementaemia, leukocytosis, elevated ESR, CRP, serum creatinine, BUN, amylase
    • Urine: pyuria, eosinophiluria, heme positive urine or stool
35
Q

Cholesterol emboli histo

A
  • Cholesterol emboli: elongated clefts within lumina of small vessels –> clefts are from dissolution of cholesterol crystals during the fixation process
  • neutrophils, eosinophils and mononuclear cells in the arterial walls within 24-48 hours, multinucleated histiocytes within 3-6 days (make sense)
36
Q

Cholesterol emboli ddx

A
  • abrupt onset should worry those about cholesterol or oxalate embolism
  • retiform purpura, especially when it occurs distally in concert with extensive distal livedo reticularis, is especially suggestive of this diagnosis
  • Acral cold occlusion syndromes need to be considered
37
Q

Cholesterol emboli rx

A
  • supportive, if possible surgical bypass or endovascular stent grafting
  • aspirin, antiplatelets, statins, discontinuation of anticoagulation
  • severe renal damage –> initiation of anticoagulation
  • systemic steroids
  • iloprost
  • hyperbaric oxygen
38
Q

Oxalate Embolus path and epi

A
  • Really rare, occurs in association with primary hyperoxaluria
    • rare enzyme deficiency
    • increased oxalaic acid accumulation
39
Q

Oxalate Embolus clinical

A
  • Childhood: urolithiasis –> deposits in the kidney –> renal failure
  • Once renal failure occurs, then embolus usually occurs
  • death by age of 20 is not uncommon
  • Secondary or acquired may result from taking oxalate precursors, increased absorption, pyridoxine deficiency, impaired renal excretion or bowel disease (Crohns)
  • Cutaneous:
    • acrocyanosis
    • Raynaud
    • peripheral gangrene
    • acute cutaneous necrosis
    • livedo reticularis
    • erythematous ulcerated nodules
    • miliary calcified deposites
    • cutaneous calciphylaxis like presentation –> can be confusing because also renal failure
40
Q

Oxalate Embolus histo

A
  • yellow-brown birefringent crystals in a rectangular or radial pattern within and around vessels in the deep dermis and subcutaneous tissue
  • crystals are yellow to golden brown in routinely stained sections, and birefringent under polarized light
  • stain with alizarin red at pH 7
  • no calcium deposition
41
Q

Oxalate Embolus ddx

A
  • cholesterol embolus
  • cutaneous calciphylaxis
  • other retiform purpura and livedo reticularis
42
Q

Oxalate Embolus rx

A
  • Type 1 primary hyperoxaluria without renal failure: oral pyridoxine
  • Type 2: hydration and alkalinization of the urine
  • no point doing a transplant without fixing the underlying issue
  • hepatic transplant may reverse it
43
Q

Atrial myxoma

A
  • are, 3rd - 6th decade of life. Constitutional symptoms: fever, malaise, arthralgia, weight loss, blood flow obstruction, embolic phenomena
    • Cutaneous: acral papules, purpuric, serpiginous or annular violaceous fingertip lesions, splinter haemorrhages, livedo reticularis, Raynaud, toe necrosis, malar flush, distal petechiae
    • Carney complex: multiple early onset cardiac myxomas
44
Q

Neonatal Purpura Fulminans

A
  • Homozygous deficiency or severe dysfunction of protein C or protein S leads to neonatal purpura fulminans
  • Its interesting because if they have deficiency of antithrombin 3 then they get DVTs and PEs but minimal cutaneous findings
  • Clinical: non-inflammatory retiform purpura –> large scale cutaneous and limb necrosis, and visceral organ involvement
  • Often born with cerebral thrombosis or retinal vessel occlusion with congenital blindness
  • Can get acquired from group B strep infections
  • Rx: intravenous protein C or fresh frozen plasma as initial treatment, then warfarin or LMWH, followed by tapering of factor replacement. they are then anticoagulated for life
45
Q

Warfarin necrosis

A
  • Abnormal gamma-carboxylation by the liver of vitamin K sensitive factors –> 2, 7, 9, 10, protein C and, could also get from severe vitamin K deficiency
  • shortest half lives are factor 7 and protein C –> factor 7 is needed to switch to procoagulation
  • so in warfarin necrosis, the procoagulant system takes longer to reach its low point equilibrium than protein C dependant anticoagulation does
  • Starts 2-5 days after starting warfarin without heparin, more likely to occur if loading doses occur, and is when the protein C drops
  • 4X higher in women, peak incidence 60-70s
  • late onset warfarin necrosis is also a thing, for people with poor compliance or inappropriate dosing, liver function alteration or drug interactions
  • Clinically:
    • areas with lots of subcut fat: breast, hip, buttock or thigh
    • pain, followed by well-demarcated erythema –> rapidly becomes haemorrhagic and necrotic
    • partial retiform or branching purpura typically can be seen within or at the margin of the cutaneous lesions
  • Biopsy: thrombosis of most of the dermal vessels
  • Rx: stop warfarin, start vitamin K and heparin, and protein C replacement
46
Q

Warfarin associated venous limb gangrene

A
  • malignancy and HITs –> venous limb ischaemia and gangrene
  • malignancy –> platelet consumption and coagulopathy
  • INR is elevated as well
  • persistent thrombin generation
47
Q

Purpura fulminans with sepsis

A
  • Meningococall infection: meningococcus’ ability to bind directly to endothelial receptors via its type 4 pili
  • Can also occur with S aureus, HIb and a few others
  • In bubs most commonly from GBS
  • Septic patient with DIC:
    • retiform purpura can be the first sign –> inability of protein C-thrombodulin pathway to prevent clot propagation
48
Q

Purpura fuliminans post infection

A
  • Children post group A strep, varicella zoster or HHV6 –> acquire and antibody that inhibits protein S function
  • occurs 7-10 days after initial infection
  • Rx: would ideally like to treat with protein S, but there is no such thing really, so trial plasma exchange, plasmapharesis, plasma replacement + LMWH and sometimes IVIG
49
Q

Antiphospholipid Antibody/ Lupus Anticoagulant Syndrome Diagnosis

A

Diagnosis - Sapporo-Sydney Criteria
You need at least 1 clinical and 1 lab criteria:
Clinical:
1. Vascular thrombosis –> can occur anywhere
2. Pregnancy morbidity
1. 1 or more unexplained foetal death after 10 weeks
2. Or 1 or more premature births of morphologically normal neonates before 34 weeks due to eclampsia/pre-eclampsia/placental insufficiency
3. 3 ore more spontaneous abortions
Lab criteria:
1. Anti-cardiolipin antibodies, IgM or IgG
2. Lupus anticoagulant
3. Anti beta-2 glycoprotein

50
Q

Antiphospholipid Antibody/ Lupus Anticoagulant Syndrome epidemiology

A
  • Females ++
  • mean age 42 +/- 14 years
  • Primary: 53%, secondary lupus 36%, lupus like sydnromes 5%
  • Patients with lupus: more episodes of arthritis, livedo reticularis, thrombocytopaenia, leukopenia
  • Females more likely to have arthritis, livedo reticularis, migraines
  • Men: MI, epilepsy, arterial thrombosis
51
Q

Antiphospholipid Antibody/ Lupus Anticoagulant Syndrome pathogenesis

A

multiple mechanisms for anti-phospholipid antibodies mediating thrombosis –> interference with release of prostacyclin, protein C and S pathways, activation of platelets by interacting with platelet membrane phospholipids, etc

52
Q

Antiphospholipid Antibody/ Lupus Anticoagulant Syndrome clinical

A
  • Cutaneous:
    • Livedo reticularis - 24%
    • Leg ulcers 5.5%
    • Pseudovasculitic lesions 3.9%
    • Digital gangrene
    • Cutaneous necroiss
    • Splinter haemorrhages
    • Acral livedo reticularis
    • Livedoid vasculopathy or Degos-like lesions
    • Anetoderma like lesions with microthrombosis
    • Raynaud
    • Behcet like
    • PG like
    • Nail fold ulcers
    • Pseudo-Kaposi sarcoma
  • Extra-cutaneous
    • DVT/PE
    • CNS
    • Catatrophic APLS - precipitated by surgery, drugs, discontinuation of anticoagulants, infections
  • Also quite possibly can have seronegative group
53
Q

Antiphospholipid Antibody/ Lupus Anticoagulant Syndrome path and lab investigations

A
  • Antiphospholipid antibodies and lupus anticoagulants are detected by different assays - if positive for both its because they actually probably are
  • Lupus anticoagulant
    • most specific
    • poorly predictive of thrombosis
  • Anti-cardiolipin antibodies
    • more positive than lupus
    • specificity for clinically significant disease is lower
  • Histo:
    • non-inflammatory thrombosis of small dermal vessels
54
Q

Antiphospholipid Antibody/ Lupus Anticoagulant Syndrome ddx

A
  • in lupus, APLS is particularly likely to present as persistent moderate to extensive livedo reticularis or as livedoid vasculopathy
  • Catastrophic may mimic DIC or ADAMTS13 deficiency
  • Levamisole adulterated cocaine: neutropenia, aPL antibodies, ANCA
55
Q

Antiphospholipid Antibody/ Lupus Anticoagulant Syndrome rx

A
  • Heparin and chronic anticoagulation
  • Aspirin for arterial events or stroke
  • Lupus: antimalarial
  • Catastrophic: systemic steroids, plasma exchange, IVIG, ritux, cyclophosphamide, eculizumab
56
Q

Sneddon syndrome epi

A
  • F>M

- third or fourth decade of life

57
Q

Sneddon syndrome pathogenesis

A
  • often considered a manifestation of APLS, but not always positive antibodies
  • Distinctive vasculopathy of smaller arteries and larger arterioles - particularly skin and brain
  • Significant overlap with autosomal recessive disorder ADA2 deficiency
58
Q

Sneddon syndrome clinical

A
  • persistent, widespread livedo racemosa –> can precede neuro for many years
  • labile hypertension
  • CNS disease
  • Hx foetal loss
  • Raynauds
  • those who are aPL antibody negative are less likely to have seizures, mitral regurg, thrombocytopaenia but more likely to have larger pattern livedo reticularis
59
Q

Sneddon syndrome histo

A
  • take the biopsy from normal appearing skin the centre of livedo reticularis
  • endothelial inflammation, subendothelial myointimal hyperplasia, occlusion (partial or whole) of involved arterioles
60
Q

Sneddon syndrome ddx

A
  • Other livedo racemosa ddx
  • ADA2 deficiency –> paeds
  • make sure to test aPL antibodies
61
Q

Sneddon syndrome rx

A
  • Warfarin, although not routinely effective
  • Systemic steroids or immunosuppressants not helpful either
  • in those who are aPL negative, antiplatelets were just as effective so use aspirin/clopidogrel
62
Q

Livedoid vasculopathy epi

A
  • young to middle aged women
  • can be divided into:
    • Primary
    • Secondary –> associated with varicosities, etc
63
Q

Livedoid vasculopathy pathogenesis

A
  • unknown, believed to be alteration in local or systemic control of coagulation with formation of fibrin thrombi focially wihtin superficial dermal blood vessels
  • number of prothrombotic factors has been associated with this syndrome lijke protein C and S, factor 5 leiden, etc
64
Q

Livedoid vasculopathy clinical

A
  • painful, persistent and often punched-out ulcerations on the legs –> particularly the malleoli in women
  • some patients may develop retiform or stellate purpura or ulcer extension
  • heals with white atrophic scars with peripheral telangiectasias
  • 50% –> associated prothrombotic abnormality has been noted
65
Q

Livedoid vasculopathy ddx

A

Antiphospholipid antibody syndrome

atrophie blanche like lesions: APLS, vasculitis, sickle cell disease, hydroxyurea related leg ulcers

66
Q

Livedoid vasculopathy histo

A
  • mild peri-vascular lymphocytic infiltrate
  • extravasated red cells surrounding superficial dermal vessels with hyalinized walls and luminal fibrin deposition
  • IF non-specific: IgM, C3 may be within vessel walls
67
Q

Livedoid vasculopathy rx

A
  • anticoagulants as monotherapy

- other options: anabolic steroids, IVIG, antiplatelets

68
Q

Malignant atrophic papulosis epi

A
  • females, 20s-40s

- can be familial

69
Q

Malignant atrophic papulosis pathogenesis

A
  • small vessel vasculopathy –> vaso-occlusive disorder
  • several diseases can mimic it: APLS, lupus, DM
  • Two forms:
    • Systemic - dysregulation of interferon alpha and C5-9 membrane attack complex
    • Benign - skin limited
70
Q

Malignant atrophic papulosis clinical

A
  • Cutaneous:
    • crops of small 2-5 mm erythematous papules on the trunk or extremtiies, these evolve over 2-4 weeks with central depression
    • porcelain white scar often with a rim of telangiectasias and appearance similar to atrophie blanche
    • typically precede systemic manifestations
  • Gastrointestinal: bowl perforation
  • CNS manifestations
  • Probability of having benign form of disease 70%, after 7 years of skin limited disease then icnreases to 97%
71
Q

Malignant atrophic papulosis histo

A
  • Wedge shaped area of ischaemic dermis with a sparse perivascular lymphohistiocytic infiltrate at the edge of the ischaemic area
  • atrophic but slightly hyperkeratotic overlying epidermis
  • Oedema and mucin in the ischaemic dermis
  • Late stage sclerosis may be seen
  • base of lesion: vascular damage with thrombosis
72
Q

Malignant atrophic papulosis ddx

A
  • lupus, DM

- APLS

73
Q

Malignant atrophic papulosis rx

A
  • no proven treatment for idiopathic
  • Aspirin, dipyridamole, eculizumab (decreases C5-9 membrane attack complex deposition) and trepostinil
  • Mixed results with IVIG

Derm (57 decks)

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